BIOLOGICAL POLLUTION - Marine Pollution: What Everyone Needs to Know - page 199

What are some invasive marsh plants and what harm
do they do?
The common reed Phragmites australis (Figure 10.4) is native
to the United States. However, a different genetic strain from
Europe is a major invader in East Coast brackish and freshwa-
ter marshes. It outcompetes native plants, replacing diverse
plant assemblages in freshwater and brackish wetlands. In
brackish marshes its effects on aquatic animals vary; some spe-
cies are not affected by its takeover of the marsh, while killifish
(mummichogs) (and people) clearly prefer the native cordgrass,
Spartina alterniflora. Detritus from Phragmites gets into food
webs the same as the detritus from Spartina , so it has a similar
trophic function. The invader can sequester pollutants better
than the native cordgrass, and is an effective buffer against
storm surge, so it has both negative and positive effects.
The Atlantic cordgrass Spartina alterniflora, , native to the East
Coast of the United States, is a highly valued native. It has been
planted elsewhere for coastal protection and sand dune sta-
bilization. However, when moved to new areas, such as the
Figure 10.4 Common reed Phragmites australis (photo from Peddrick Weis)